Remove fs2 dependency and update Rust to 1.89 (#15764)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR removes the crate fs2 and updates Rust version to 1.89.
*Why?*
Crate fs2 is unmaintained for a long time now and has unfixed issues.
Especially it doesn't build on AIX, which is the reason I started fixing
it.
*How?*
I removed fs2 and replaced it by std:fs:File methods.
## Test Plan
<!-- How was it tested? -->
- I built it on Windows and AIX only.
- I did not test the artifacts.
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Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
